The Kallisto Audio Sinfonia 300 Single Ended Power Amplifier

[An Audiophilia Archived review -- from 2006 and still current - Ed]
The Chinese are not coming, they’re here. The sleeping giant is no more. It has awakened with the force of strong money markets, a huge, talented workforce, an entrepreneurial spirit that would make an arch Republican blush, and has even captured the heart of that most heartless of beasts, Wal-Mart!

The Chinese have always sourced parts to the audio industry, at least for those who wanted them cheap and cheerful, with emphasis on the cheap. The higher end of the high end always eschewed them, but mid fi dreck and clunkers ate up the stuff. In the last ten years, though, things have changed. Chinese designers have caught on to what audiophiles want: great sound, great looks, and amazing value. Kit makers abounded and companies like Jolida made a splash at shows by offering real value for money. Where Jolida led, others followed. Lots of them.

Kallisto Audio is based in Toronto, but the designers are Chinese born and trained and the parts are sourced from China. It is the second tube amplifier that I have received for review recently from a Sino/Canadian source. This Kallisto model is called the Sinfonia and spouts the Holy Grail of tube tech, Class A, 300B tube Single Ended design.

Bruce Ng, CEO of Kallisto Audio, was kind enough to deliver the amp to my house, discuss its design and set it up for me. The large footprint supports a very smart looking piece — aluminum chassis with chunky accents of light copper. The transformers are covered with brushed silver towers and the tubes are naked to the world.

Even though the Sinfonia was burned in for 72 hours on the test bench, I played a CD with a decent amount of signal for 48 hours (precisely!) to be sure of a good break in. It boasts a heavy duty power supply and point to point wiring on all signal paths. The tube compliment is 2 X 5U4g, 2 X 6SN7, 2 X 6SL7 and 2 300Bs. They didn’t put a foot wrong during the three-month review period.

Designing a low power (7.5 watts a side), 300B single ended amplifier is no mean feat. My first question to Ng was from which tube manufacturer does Kallisto source its parts. Sovtek and Electro-Harmonix, it turns out. Western Electric is the known benchmark for these wonderful tubes, but manufacturers such as KR and Svetlana also make fine versions of them. The Western Electrics, however, are double the price of the well-made KRs, which are double the price of the run of the mill variety. Many tube gurus suggest that they can hear significant differences in the sound of different 300Bs in the same amplifier. I did not substitute 300Bs to test the tube experts’ theories.

Out of the box, the Kallisto Sinfonia sounded quite flat and two-dimensional. Definitely not my experience with SET amps. After a little net research (some great articles out there), many suggested that the tubes must have at least 200 hours on them before they sound their best, maybe 300. Gulp! Back into soft play mode it went. Luckily, I was off to New York City for a week on business, so I asked my wife to keep an eye on the Sinfonia while it amplified Reference’s Symphonic Dances ad nauseum!

At 7.5 watts a side, a prospective purchaser needs to pair the Sinfonia with a very efficient speaker. My reference fabaudio Model 1s are 98dB, which was just fine, even on large orchestral works. I would not wander much below 95dB if one of these amplifiers is in your future. A Lowther or Beauhorn would be ideal. With this type of speaker, the Kallisto could slam out some Sex Pistols, not that any sane person would! I did have them hooked up to the ASW Genius 400s (review forthcoming), which are 93dB. No problem here, either. If you live day in, day out with a lower dB speaker, and can’t resist either the look or price of the Kallisto, make sure to demo the amplifier in your home setting to be sure they are a good match.

For my fabs, the Sinfonia was an easy test. After nearly two hundred hours, the sound did loosen up considerably. I could hear the sound spectrum for which 300B SETs are justifiably loved: sweet highs, very involving midrange and a balanced bass. Width and depth was good, if not quite as fine as heard from the much more expensive SET amplifiers from KR Audio (among the best I’ve heard), but definitely effective enough to give a true picture of the recorded space.

The new Symphonic Dances recording from Reference (the old Reference version by the Minnesota Orchestra is already super demonstration level, an A List recording par excellence) sounded alive and powerful. As such, the Sinfonia easily disseminated the sound from Utah’s Abravanel Hall. Very well played, if not quite as good as Minnesota, and in a more reverberant space.

My old jazz demo standby, Power of Three, had the Kallisto layering the instruments as they should – Wayne Shorter’s vibrant tenor far right, Michel Petrucciani’s piano centre back and Jim Hall’s guitar close left, but darting front to back depending upon solo or accompaniment. The Sinfonia really had this CD swinging. The midrange quality was much in evidence, especially on the opening track, Limbo, which spotlights Shorter’s incredibly fast technique and breath tone. Not all amps, especially at this price level, decipher his sound.

I tried some heavy rock, just for fun! I grabbed a burned CD from my son’s collection; Alexisonfire was as advertised. Loud, loud, loud, with very little substance or style. The good news? The Kallisto did not flinch – no backing off pounding drums or thundering bass. On the lesser efficient ASWs, Alexis was not quite so On Fire! And with a speaker around 89 or lower, Alexis would be filing for divorce.

So, the Sinfonia is no shrinking violet, even at a mere 7.5 watts. Matched to the correct speaker, it will give you a taste of the SET high life for a very reasonable USD$2700.00. Audiophiles know that under three large is a very low price for this type of technology especially as wrapped in this gorgeous frame. If just under eight excellent watts will suit your needs, arrange an audition. Recommended!